Re: Bugreport - submodules are fetched twice in some cases

[Glen Choo <chooglen@google.com>]

> FWIW, without "--all", we do not make an extra fetch at all, with
> the current code or with code as ancient as v2.5.0

Aha, the reason why I wasn't able to override "--recurse-submodules" is
that I didn't notice add_options_to_argv() was setting
"--recurse-submodules" for each of the 'inner' fetch-es in
fetch_multiple().

So a PoC fix might look like this

----- >8 --------- >8 --------- >8 --------- >8 --------- >8 ----

diff --git a/builtin/fetch.c b/builtin/fetch.c
index e3791f09ed..d42646e68c 100644
--- a/builtin/fetch.c
+++ b/builtin/fetch.c
@@ -1856,10 +1856,6 @@ static void add_options_to_argv(struct strvec *argv)
 		strvec_push(argv, "--force");
 	if (keep)
 		strvec_push(argv, "--keep");
-	if (recurse_submodules == RECURSE_SUBMODULES_ON)
-		strvec_push(argv, "--recurse-submodules");
-	else if (recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND)
-		strvec_push(argv, "--recurse-submodules=on-demand");
 	if (tags == TAGS_SET)
 		strvec_push(argv, "--tags");
 	else if (tags == TAGS_UNSET)
@@ -1942,8 +1938,7 @@ static int fetch_multiple(struct string_list *list, int max_children)
 			return errcode;
 	}
 
-	strvec_pushl(&argv, "fetch", "--append", "--no-auto-gc",
-		     "--no-write-commit-graph", NULL);
+	strvec_pushl(&argv, "fetch", "--append", "--no-auto-gc", "--no-write-commit-graph", "--recurse-submodules=false", NULL);
 	add_options_to_argv(&argv);
 
 	if (max_children != 1 && list->nr != 1) {
@@ -2271,6 +2266,10 @@ int cmd_fetch(int argc, const char **argv, const char *prefix)
 			max_children = fetch_parallel_config;
 
 		add_options_to_argv(&options);
+		if (recurse_submodules == RECURSE_SUBMODULES_ON)
+			strvec_push(&options, "--recurse-submodules");
+		else if (recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND)
+			strvec_push(&options, "--recurse-submodules=on-demand");
 		result = fetch_submodules(the_repository,
 					  &options,
 					  submodule_prefix,